you can stop the server service. or you can disable netbios over tcpip. i
would look at the server service. also another idea is the workstaions
subnet mask change to 255.255.255.255 and leave the servers at 255.255.255.0
this should allow the servers to show up on the network and the workstations
think they are on there own network,
This can be done by setting the Startup Type for the Computer Browser
service to Manual or Disabled. Users will still see their own computer in
Network Neighborhood (after a rather long timeout), but they will not see
any other computer. This also avoids the difficulty of having to disable
NetBIOS when you may still need that protocol.